sizing down jacketed bullets

[cosmoline one]

I want to size jacketed bullets from .312" down to .308"
I have a.311 & a .308 sizer. Can I go from .312 to .308 or should I size down to .311 first?

[BK7saum]

Regardless, you my have accuracy issues with the bullets after sizing. Bullets are swaged up in diameter for a reason. Lead springs back less than red brass jacket/guilding? material.

Your lead cores will likley be loose inside the jacket, which could result in accuracy problems.

That said, it may not be an issue for you, but i w9uld use case lube and take them down in 2 steps instead of one, even if the first was only 0.001"

[kaiser]

I have been sizing .323 to .318 for several decades now by using a cast sizing die; a steel rod with an end that covers the base; a hammer; and sizing lube. It was suggested by some "old timer" (older than me at the time) to use only 200gr Speer "Hot Core" jacketed bullets due to possibly loosening the "core" of other brands. I've shot many a deer using this "downsized" bullet with no adverse effect, or jacket separation of any of the recovered bullets. I'm not driving them much more than 2300fps out of an old Drilling, which probably accounts for them staying intact. I would prefer to use an intermediate step in downsizing, as suggested, but have not found a suitable die for that operation. I have also tried this same operation with 175gr. Sierra bullets, but have not used them on any game animal to date. (I do remember one of the well known "gun scribes", at the time. recommending that one should not downsize more that .003 for best results.)

[toallmy]

I shoot with a buddy that has a 333 Jeffrey , he sizes 338 bullets down mainly because that's the only way he can get any , but they work out well . One pass through a home made die - with lube .

[cwlongshot]

I have sized large amounts of .358/357 down to .356/355 for use in the 350 Legend.
Specifically 150g Remington and 180 Hornady SSP. Usually two passes and it was good. Accuracy was seemingly unaffected. That is to say these sized down shot just as well smaller in the 350 as they once did in the 357 Maxi.

Your results may very.

CW

[smithnframe]

I size .338 bullets down to .329 for a 95 Steyr I have with a Lee sizing die with no problem!

[JRLesan]

Had a set of .406 dies made years ago for a 1910 Winchester. Have sized those jacketed bullets (not cartridge case jackets but rather factory handgun jackets) down to .401 for use in a 10mm pcc with no separation or accuracy issues, so far. I was at first concerned about (so called) jacket 'springback' but no such thing occurred...

[hpbear101]

I also size .338 to .329, I spray a little case lube in a ziploc bag, tumble them around a bit then size.

[HD.375]

some guys swaged down some 170gr 321 ?or .323 i think, down to .316 or so for me to use in 303 british Rugr 1...
speer hot cors.

i also wanna swage down some 313 cast for 30-06

[Uncle Grinch]

When I had my 7.7 Carcano I would swage .308 jacketed bullets down to .300 with a Lee .277 die that my gunsmith opened up for me. I replaced my press handle with one about a foot longer and used plenty of lube.

[cosmoline one]

I appreciate all trhe replies, but just to be clear , are you making thesse reductions in one pass through a sizer ?

[JRLesan]

Affirmative on .406 to .401; one pass...

[SSG_Reloader]

I've sized tons down straight from .312 down to 308 without issue for my plinking rounds.